Synthesis,self-assembly and photo-responsive behavior of AB2 shaped amphiphilic azo block copolymer

In this work, we report the synthesis of AB2 shaped amphiphilic azo block copolymer by macromolecular azo coupling reaction. The product and intermediates were characterized by various methods. The selfassembly in selected solvents and photo-responsive behavior of the copolymer were studied by means of UV–vis spectrophotometry and TEM. Spherical aggregates can be obtained by gradually adding water into the solution of this amphiphilic azo block copolymer. Upon irradiation with polarized UV(365 nm)light, the aggregates can be elongated in the polarized direction.     

CdS quantum dot sensitized p-type NiO as photocathode with integrated cobaloxime in photoelectrochemical cell for water splitting

CdS sensitized NiO electrode was used as the photoactive cathode in a photoelectrochemical cell for water splitting,avoiding the use of a sacrificial electron donor.Photocurrent increment under visible light irradiation was observed after integration of[Co（dmgH）₂（4-Me-py）Cl]（1） to the photocathode,suggesting 1 could accept electrons from photoexcited CdS for water reduction and NiO could move the holes in the valence band of CdS to anode for water oxidation.     

Thermal Conversion of Methane to Formaldehyde Promoted by Gold in AuNbO3+ Cluster Cations

In addition to generation of a methyl radical, formation of a formaldehyde molecule was observed in the thermal reaction of methane with AuNbO₃⁺ heteronuclear oxide cluster cations. The clusters were prepared by laser ablation and mass‐selected to react with CH₄ in an ion‐trap reactor under thermal collision conditions. The reaction was studied by mass spectrometry and DFT calculations. The latter indicated that the gold atom promotes formaldehyde formation through transformation of an Au?O bond into an Au?Nb bond during the reaction.     

Reversibly light‐responsive biodegradable poly(carbonate) micelles constructed via CuAAC reaction

Light‐responsive poly(carbonate)s PEG₁₁₃‐b‐PMPC_n‐SP were synthesized via copper catalyzed azide‐alkyne cycloaddition reaction between azide‐modified spiropyran (SP‐N₃) and amphiphilic copolymer PEG₁₁₃‐b‐PMPC_n. PEG₁₁₃‐b‐PMPC₂₅‐SP can self‐assemble to biocompatible micelles with an average diameter of ～96 nm and a critical aggregation concentration of 0.0148 mg mL^?1. Under 365 nm UV light irradiation, the characteristic absorption intensity of merocyanine (MC) progressively increased and most of the micellar aggregations were disrupted within 10 min, suggesting the completion of the transformation of hydrophobic SP to hydrophilic MC. Subsequent exposuring the micelles to 620 nm visible light, spherical micelles aggregated again. The light‐controlled release and re‐encapsulation behaviors of coumarin 102‐loaded micelles were further investigated by fluorescence spectroscopy. This study provides a convenient way to construct smart poly(carbonate)s nanocarriers for controlled release and re‐encapsulation of hydrophobic drugs. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 750–760     

Facile preparation of boronic acid‐functionalized magnetic nanoparticles with a high capacity and their use in the enrichment of cis‐diol‐containing compounds from plasma

The use of bronate affinity adsorbents is a new separation method that appeared recently with great potential for specific extraction of cis‐diol‐containing compounds. In this work,a new strategy for the facile construction of boronic acid‐functionalized Fe₃O₄ magnetic nanoparticles (Fe₃O₄@FPBA MNPs) with a high capacity was described. The extraction capacity of the Fe₃O₄@FPBA MNPs was determined to be 66.0 ± 2.7 µmol/g for catechol and 80.6 ± 2.0 µmol/g for dopamine, being higher than that for the reported methods. The Fe₃O₄@FPBA MNPs were used to extract four cis‐diol drugs: caffeic acid isopropyl ester, caffic acid bornyl ester, isopropyl 3‐(3,4‐dihydroxyphenyl)‐2‐hydroxypropanoate and 3‐(3, 4‐dihydroxyphenyl)‐2‐hydroxylpropionic acid – from the spiked rabbit plasma, and the recoveries of four drugs were between 87.29 and104.37% with relative standard deviations ranging from 1.34 to 8.81%. Under the most favorable conditions, the solid‐phase extraction combined with HPLC‐UV for the analysis of four drugs in plasma could eliminate interferences from endogenous components of the biological fluids and exhibited sufficient precision and accuracy. These results showed that the prepared Fe₃O₄@FPBA MNPs were qualified for efficiently enriching and determining the trace cis‐diol substances from biological samples. Copyright © 2014 John Wiley & Sons, Ltd.